Download Visual Studio Express 2008 now

[Martin v. Loewis]

Microsoft has just released Visual Studio 2010, along with its free (of
charge) Express edition. Following a tradition, they are likely to
withdraw support and availability for VS 2008 Express some time in the
future.

Python 2.6, 2.7, and 3.1 are all built with that release (i.e. 2008).
Because of another long tradition, Python extension modules must be
built with the same compiler version (more specifically, CRT version) as
Python itself. So to build extension modules for any of these releases,
you need to have a copy of VS 2008 or VS 2008 Express.

If you are planning to build Python extension modules in the next five
years, I recommend that you obtain a copy of VS Express, just in case
Microsoft removes it from their servers. As mentioned, it's free of
charge. When downloading it for later use, it's probably best to get the
offline ISO image release, available from

http://www.microsoft.com/express/Downloads/#2008-All

Disclaimer: I'm not connected with Microsoft or its release process. Any
claim on future actions that Microsoft may take is purely hypothetical.

Regards,
Martin

 

[Michel Claveau - MVP]

Hi!

Thanks for this idea.

Michel Claveau

 

[Irmen de Jong]

If you are planning to build Python extension modules in the next five
years, I recommend that you obtain a copy of VS Express, just in case
Microsoft removes it from their servers.

Thanks for the idea Martin. However I've changed the post title a little because at
first I skipped this post because I thought that it was product spam ;-)

Irmen de Jong.

 

[Neil Hodgson]

Martin v. Loewis:

Python 2.6, 2.7, and 3.1 are all built with that release (i.e. 2008).
Because of another long tradition, Python extension modules must be
built with the same compiler version (more specifically, CRT version) as
Python itself. So to build extension modules for any of these releases,
you need to have a copy of VS 2008 or VS 2008 Express.

Is it too late for Python 2.7 to update to using Visual Studio 2010?
It is going to be much easier for people to find and install the current
version of VS than the previous. There is still more than 2 months left
before 2.7 is planned to be released.

Neil

 

[Lie Ryan]

Microsoft has just released Visual Studio 2010, along with its free (of
charge) Express edition. Following a tradition, they are likely to
withdraw support and availability for VS 2008 Express some time in the
future.

If only Python could do that, just pull the plug out and not offer
archaic versions for download. If that has been the tradition all along
probably people would be rushing to download Python 3 when it's hot and
porting all their code in fear of using a no longer supported compiler
instead of complaining how they're still using python 1.5 and now
there's python 3.0 breaking compatibility.

I guess I'm glad that whatever python program I wrote now would still be
easily runnable with no change in twenty years or so.

 

[Robin Becker]

On 12/04/2010 21:36, Martin v. Loewis wrote:
...........

If you are planning to build Python extension modules in the next five
years, I recommend that you obtain a copy of VS Express, just in case
Microsoft removes it from their servers. As mentioned, it's free of
charge. When downloading it for later use, it's probably best to get the
offline ISO image release, available from

http://www.microsoft.com/express/Downloads/#2008-All

...........

Is it sufficient to download just the setup program vcsetup.exe or do people
need to obtain the offline iso which presumably has the full content in it.

 

[Lie Ryan]

On 12/04/2010 21:36, Martin v. Loewis wrote:
...........
...........

Is it sufficient to download just the setup program vcsetup.exe or do
people need to obtain the offline iso which presumably has the full
content in it.

As I remember it when installing VS Excpress a few years back, the thin
installer is just a download manager so you should get the full
installer if you want to insure yourself from Microsoft pulling the plug
out.

 

[Robert Kern]

Am I missing something here? I have heard this before, but I have built
extension modules many times under windows (using Cython) and never once
used a MS product. I've just had to change a distutils config file to
use a different compiler (mingw32, directions here:
http://docs.cython.org/src/tutorial/appendix.html). It seems to work
fine. What is the basis of this claim that you need MS Visual Studio to
do it?

Most extensions will work okay when compiled with mingw32. However, mingw32 is
still based on MSVCRT6.dll as its C runtime. You would get errors whenever a
FILE* pointer crosses over the boundary. distutils will tell it to link with the
CRT that Python is currently built with, but some of the headers aren't up to
date for that CRT, so some C++ extensions will not work (a command C++ operation
triggers a table lookup in a static table defined in the CRT, but it differs in
size between versions).

--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
that is made terrible by our own mad attempt to interpret it as though it had
an underlying truth."
-- Umberto Eco

 

[Martin v. Löwis]

Am I missing something here? I have heard this before, but I have built
extension modules many times under windows (using Cython) and never once
used a MS product.

It's fine if your package supports being compiled with Mingw32. A lot of
source code can't be compiled this way, either because gcc doesn't
support some of the MS extensions (in particular wrt. COM), or because
Mingw32 doesn't provide the header files (in particular wrt. C++), or
because linking with a library is necessary that uses the MSVC mangling,
not the g++ one (again, for C++).

Code written in Cython should work fine with gcc indeed.

It seems to
work fine. What is the basis of this claim that you need MS Visual
Studio to do it?

Just try building Mark Hammond's Win32 extensions or PythonWin with
Mingw32 to see for yourself.

Regards,
Martin

 

[Martin v. Loewis]

Python 2.6, 2.7, and 3.1 are all built with that release (i.e. 2008).

Is it too late for Python 2.7 to update to using Visual Studio 2010?

Most definitely. They have switched *again* the way they distribute the
CRT, so major changes to packaging and distutils would be required.

It is going to be much easier for people to find and install the current
version of VS than the previous. There is still more than 2 months left
before 2.7 is planned to be released.

It took us about two years to accommodate the CRT change. This time, it
will be easier, but nowhere near 2 months. I'm skeptical that the switch
to VS 2010 will be ready for 3.2.

Regards,
Martin

 

[Lawrence D'Oliveiro]

It's fine if your package supports being compiled with Mingw32. A lot of
source code can't be compiled this way, either because gcc doesn't
support some of the MS extensions (in particular wrt. COM) ...

But then such code will not be portable to anything but Windows.

... or because Mingw32 doesn't provide the header files (in particular
wrt. C++), or because linking with a library is necessary that uses the
MSVC mangling, not the g++ one (again, for C++).

Again, that would be code that’s not portable off Windows.

 

[Lawrence D'Oliveiro]

... so you should get the full installer if you want to insure yourself
from Microsoft pulling the plug out.

I wonder how many Windows users will be able to figure that out...

 

[David Cournapeau]

Again, that would be code that’s not portable off Windows.

Not really, part of the issue is that mingw uses ancient gcc (3.x
series), and g++ 3.x has poor C++ support compared to MSVC (or gcc
4.x).

There is also the issue that gcc debugging symbols are totally
incompatible with MSVC, so you cannot debug things from anything but
gdb. Gcc for win64 is also not that stable yet - when porting numpy
and scipy on windows 64, I got numerous issues with it.

None of this has anything to do with portability.

cheers,

David

 

[Martin v. Loewis]

... or because Mingw32 doesn't provide the header files (in particular

Again, that would be code that’s not portable off Windows.

Probably (although it *is* possible to write code that compiles on
Windows only with MSVC, and compiles fine on Unix with gcc).

However, I wonder what you are trying to imply: that the code is useless
if its not portable? That would be wrong: the code may well be very
useful, and enjoy great popularity, even if it runs on Windows only.

Regards,
Martin

 

[Martin v. Loewis]

... or because Mingw32 doesn't provide the header files (in particular

Again, that would be code that’s not portable off Windows.

Probably (although it *is* possible to write code that compiles on
Windows only with MSVC, and compiles fine on Unix with gcc).

However, I wonder what you are trying to imply: that the code is useless
if its not portable? That would be wrong: the code may well be very
useful, and enjoy great popularity, even if it runs on Windows only.

Regards,
Martin

 

[Robert Kern]

But then such code will not be portable to anything but Windows.

Most of such code is for Windows-specific services anyways.

--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
that is made terrible by our own mad attempt to interpret it as though it had
an underlying truth."
-- Umberto Eco

 

[Lawrence D'Oliveiro]

Just been looking at this review of Visual Studio 2010
<http://www.theregister.co.uk/2010/04/26/blowing_bubbtles/>:

... the 2GB ISO was quicker to download than it was to install - not
even counting the several reboots required.

Since when do you need to REBOOT just to install a development environment?

 

[Andrej Mitrovic]

Just been looking at this review of Visual Studio 2010
<http://www.theregister.co.uk/2010/04/26/blowing_bubbtles/>:

    ... the 2GB ISO was quicker to download than it was to install - not
    even counting the several reboots required.

Since when do you need to REBOOT just to install a development environment?

Sure beats having to recompile a kernel to support 3rd party audio
drivers. But YMMV.

Although I agree, moving away from VS would be nice. Since Unladen
Swallow will eventually be merged with Python, will the dev team
consider trying out Clang as an alternative to VS?

 

[Lie Ryan]

Although I agree, moving away from VS would be nice. Since Unladen
Swallow will eventually be merged with Python, will the dev team
consider trying out Clang as an alternative to VS?

What would Unladen Swallow brings that would allow the development of
CPython to move away from VS? Isn't Unladen Swallow's goal is only to
speed up CPython. Do you mean PyPy?

 

[TerryP]

I've generally found it wise to grab the ISO images for the express
editions collection, and save it somewhere in cold storage.

Never have needed to compile Python on Windows, but some modules only
support older versions (e.g. 2.4 or 2.5), which is irksome. So it's a
good idea to have stuff setup for building extension modules by hand.